A method for thermoplastic fusion bonding was introduced using a commercial pressure cooker as a thermal bonding chamber to apply heat and pressure for polymer thermal bonding. The chamber pressure was controlled by simply modifying the regulator weight, which decided the boiling point of water in the chamber. In this experiment, Poly-Methyl Methacrylate (PMMA) was thermally bonded using the proposed technique. For PMMA thermal bonding, 52 grams of regulator weight was well matched for 26.2 kPa of chamber pressure. The corresponding boiling temperature of water to the pressure was 105.5℃, which was the glass transitional temperature of PMMA. The thermal bonding system demonstrated bonding between the PMMA sheet and PMMA film without deformation of the microchannel. The bonding strength was characterized at 195.5±1 N.

Most of the mechanical structures use bolting or spot welding for the whole structure. In recent years, bolting & rivets are used rather than the welding due to reassembly and repair. Analysis of bolted joints is so complicate that many conditions must be considered such as pre-load and contact, etc.. Bolted joint analysis is done by theoretical, experimental & numerical methods. However, numerical analysis in the bolted joint is used because the contact and stress in the joints are changed due to the pre-load. In this study, we analysis the slip and the deformation of the contact area in the joint depending on the pre-load and find the optimized bolting condition.

Abrasive jet machining (AJM) has been traditionally used for removing rusts or paints. Nowadays, this is promising technology for micro bulk machining where brittle substrate materials are used. In order to get accurate details, masks such as metal, polymer or elastomer is inevitable. Among them, photo polymer which is sensitive to the light has been attractive for it's high accuracy using photolithography. In this research, SU-8 as a photo polymer is used since it is adequate for making thick mask. So, this paper describes how to make AJM masks using SU-8 with a photolithography process, and investigates the characteristics of SU-8 masks during AJM process. Also, an example of fabrication using AJM was shown.